Young Spock has finally arrived.

Ethan Peck makes his anticipated debut as the iconic character on Thursday’s episode of Star Trek: Discovery, which finds his adopted sister, Michael (Sonequa Martin-Green), returning home to Vulcan in an effort to rescue him before it’s too late. And his arrival to the Discovery universe couldn’t come at a better time — after seven episodes of build-up filled with carefully dropped hints and nuggets.

Haunted by visions of a mysterious entity, only known as the Red Angel, the character — who was famously played by Leonard Nimoy and later Zachary Quinto — has been talked about but his present state never actually revealed. Until now. It’ll be a far different Spock than Trek fans are used to; for one thing, this iteration of the beloved character is at least a decade younger. Another obvious change? The noticeably longer hair and shaggy beard.

ET sat down with Martin-Green and Peck, who cut his teeth on the 10 Things I Hate About You TV series and is Gregory Peck‘s grandson, for a joint interview in January at the Television Critics Association press tour in Pasadena, California, where the duo — whose real-life dynamic is endearingly reminiscent of competitive siblings — discussed Spock’s long-awaited arrival, the challenges of stepping into the shoes of a revered character and the crazy fan theory involving Spock and Michael.

ET: Ethan, you’re coming into Star Trek: Discovery playing one of Trek‘s most beloved characters. Has it been daunting for you stepping into the Vulcan shoes?

Ethan Peck: Yeah, that’s the understatement of the century for me. Yeah, absolutely daunting, terrifying. I started out almost wishing I would get fired because I was like, “This is impossible. How’s this gonna happen? How’s this gonna work? Am I capable of this?” And I came into a situation that could not have been more supportive, starting with Sonequa who really sets the tone for the set and the rest of the cast, the crew — everybody was just glass half full kind of people. I remember before I took the job, before I went in on one of the final callbacks, I talked to my manager, like, “I don’t know if I can do this if it’s not in a supportive place,” because this is so scary. Not only is it Spock, who is iconic and beloved, but it’s very difficult as an actor. The work that’s done on Star Trek is very challenging and very technical so I had a lot of things to really align and get right to walk away feeling good about it. It was just an incredible experience. It was an experience of a lifetime.

Do you feel like every point in your career led to this role? Did you feel prepared to take this on?

Peck: As for peak life, peak career experience, I don’t know if anything else led me to this in my career, but I feel like I was working on the edge of my ability the whole time, which is a dream [for] anybody doing anything.

Sonequa Martin-Green: That’s a really good way to put it.

Sonequa, what has Ethan brought to the table that has elevated the character?

Martin-Green: Magic.

Peck: I’m going to plug my ears!

Martin-Green: Magic. Because this role right now, Spock right now is for Ethan, it really is. What he brings to it is obviously something no one else would be able to bring. What we all appreciated when we welcomed him, as the family member he immediately was, was his passion and was his fortitude because he had such a sense of honor about the role and about the franchise and he knew how important it was and he was giving his all even before he even came to set and making connections and going the extra, extra mile and we appreciated that and that’s the kind of thing that is invigorating on set.

There’s a company of people who care so deeply. This is our baby, this is our child and we give our all to it, so to have someone just like that coming in and then too, Spock just brings a level of gravitas. He firms up that connected tissue between us and our central nervous system, which is the canon, so you sort of get a chance to look at the present moment and the past at the same time when you see him because you almost see the totality of the canon because he’s arguably the most beloved character in the canon and all of sudden you see a picture of what you’re doing, you’re like, “Oh my goodness, we’re doing Star Trek right now!” And he makes it tangible for you. And you’ll see, he’s a beast.

Peck: Thanks, Sonequa. It’s a blessing for someone coming on that’s new to have to walk into the world that you guys have already created. If I have to start off, I can’t imagine the burden you felt starting off brand new without the world created. I walk into a world and that’s a huge gift as an actor, especially taking on a role like this, coming into a world that’s been well-established.

In a recent episode, we learn that Spock was accused of murdering three doctors and that he’s not in the right frame of mind. And there’s clearly tension between Michael and Spock. What can you tee up ahead of Spock’s debut?

Martin-Green: We have to give credit to the writers and producers for even the existence of this relationship. I love that I, as Michael Burnham, get to be Spock’s surrogate sister, are you kidding me? It’s incredible and automatically on the page, it’s a very interesting dynamic, and very magnetic, and very complicated, and very emotional, and it’s pretty rich. The only thing we don’t have is a sexual connection…

I saw the theories about a Michael and Spock sibling romance and was like, “What?!

Martin-Green: Exactly! They’re like, “Oh, Spock must have developed sexual feelings for Michael,” and we know that from the Kelvin timeline and the J.J. Abrams films that he likes black women.

Peck: What?

Martin-Green: There’s none of that. We are not estranged because of anything like that, but as far as the brother-sister connection is concerned, the traditional one, we really explore how difficult family is with this relationship.

Peck: It’s super grounded and I think that really grounds our reality too because that’s such a universal conflict we all face is the conflict between members of a family, within a family. There’s a lot left unresolved between Spock and Burnham that you’ll get to see unravel to the next season.

Their mother, Amanda, mentions something incredibly illuminating about how she and Sarek raised Michael and Spock differently — that she wasn’t the mother Spock needed her to be.

Peck: (joking to Martin-Green) You got all the love, didn’t you?

Martin-Green: (jokingly responding) What did you say?

Peck: You got all the love, didn’t you?

Martin-Green: You know what…

Peck: (laughing) We have a friendly competition going on, a sibling competition.

Martin-Green: And I usually win.

What is the off-set dynamic between you guys?

Martin-Green: We were immediately brother and sister, it was sweatless and we call each other sib and we compete and I usually win.

Peck: (laughing) I’m always right.

Martin-Green: The crazy thing is he is sometimes and it’s really annoying and he also does win our competitions sometimes too.

What kinds of competitions are you talking about?

Peck: Competitions of strength. Knowledge.

Martin-Green: Of linguistic ability, of space knowledge … all kinds of things.

Peck: Sonequa has a beautiful son named Kendrick… (asks Martin-Green) Oh, can I say this? (Martin-Green gives her approval.) And I always go up to him on set and whisper to him, “Kendrick, you know who the most powerful being in Starfleet is?” Because, obviously it’s Michael Burnham, but I tell him it’s Spock and so I’m converting him to the dark side.

Martin-Green: He’s always like, “You know who’s better than you are? Me.”

Peck: And he’s always like, “Oh…”

Martin-Green: And I’m like, you see, “Son, anything he tells you is a lie.”

CBS All Access
CBS All Access

This version of Spock is pretty different from what we’ve known this character to be. In what ways is he a departure from what’s been established?

Peck: I think the best way I can put it is that he doesn’t quite have the wisdom that he will have in the future. He’s younger and wisdom is a result of accepting pain that you have in your life and this will be a period of discomfort for him and so that conflict between logic and emotion will be much more on the surface.

I spoke to Anson Mount earlier this year and he mentioned the incredible research you did in preparing for this role. He said that you read Leonard Nimoy’s biography, found a blueprint of the Enterprise. How deep did you go?

Peck: I went as deep as I could. I met with the Nimoy family, which was not just research but being blessed and being given the gift of validation, like good luck, we believe in you, be curious. I read I Am Not Spock and I Am Spock and watched a bunch of the original series, but there was a point where I actually stopped researching where I felt like I built my ship and now it’s time to sail because I didn’t want to begin mimicking. The whole point was to capture who Leonard Nimoy’s Spock was and internalize that and sort of regurgitate it in my own way. And with the great writing that we have which immediately differentiates him… you’ll see.

Having Pike in the picture, I feel like he is such a departure from Lorca. I’m just waiting for the other shoe to drop and for him to betray everybody and turn out to be an evil person.

Martin-Green: I know. That’s the same way the crew of the USS Discovery feels. Yeah, there’s a little bit of residual anxiety from dealing with Captain Lorca. We’re quite a departure, our show, from the rest of the franchise and we’re doing our best to be as new, yet familiar as we can at the same time and so what I love about bringing on these big, bright characters from the canon that are so beloved is that it automatically puts you in that pocket, and it helps people connect the dots honestly because we pull from the canon, that is our foundation, that is the ground we stand on. But to see these people that are so legendary in the canon and to see us interacting with them automatically connects that dot for you, I feel. I’m gonna remind you that we are a part of this franchise, that we’ve been trying to do in our own new, fresh way. So I love it.

My last question for you is about Michael and Tyler’s complicated situation. What’s going on there?

Martin-Green: Honey, it’s very difficult, and it’s very tumultuous and confusing for the both of them because they are deeply in love with one another but they keep finding themselves separated, they keep finding themselves with this chasm between them and whenever they try to get closer together it seems like something pulls them apart, so it has this sort of Romeo and Juliet essence to it because of that. But obviously, they realize that right now isn’t the best time for them to be together, they’re not whole enough to be what the other needs. Burnham certainly feels that way about Tyler and that doesn’t mean that they stop loving each other.

Tyler was being recruited by Section 31 to join the “dark side,” as they say…

Martin-Green: He’s finding who he is. It was something that really united them is they had the polarity between this side and that side within them. They connected with each other on that, so he is still deciding who he’s going to be and where he fits in. Which is really the case for everyone.

And then there’s a baby involved. It’s all very complicated.

Martin-Green: Yes, yeah, it’s exciting. It’s a lot!

New episodes of Star Trek: Discovery launch exclusively on CBS All Access on Thursdays at 5:30 p.m. PT/8:30 p.m. ET.

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